Jeff, in addition to what Jonathan said, you shouldn't rely on the TM for timeouts, particularly if your RM and TM can fail independently. If the TM fails before prepare, say, then it won't know anything about the RM (no log) and so won't ever try to timeout. In that case your RM needs to do it. Plus let's not forget: if your RM times out after agreeing to prepare then you need to return a heuristic outcome (and remember it durably until forget is called). View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4259169#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...